0
andyturner

CRW wind limits.

Recommended Posts

What are the wind limits for CRW? On the ground and at 1kft it could be blowing 18kts but higher up the wind can be doing 40kts. Providing you budget that into the spot is there anything wrong with being blown backwards over the ground while doing CRW?

Cheers,
Andy

Share this post


Link to post
Share on other sites
I think wind limits (under canopy) are irrelevant to a point… The bigger issue might be turbulence! However, the two are related. It always amazes me how turbulence can occur/increase as you pass through a certain altitude.
Birdshit & Fools Productions

"Son, only two things fall from the sky."

Share this post


Link to post
Share on other sites

Hi,

Ok so nothing is cast in stone ...yet!

From your responses it seems that turbulence is the issue that is related to wind strength. I’m assuming that turbulence is an issue because it could collapse your canopy at an inopportune moment, which could be both tedious and embarrassing, i.e. resulting in a wrap? :$

With a WL of approx 1.21 lbs/ft², if the wind below 1000ft is within spec, i.e.
Cheers
Andy
PS. Thanks for the info.

Share this post


Link to post
Share on other sites
maybe this document can help you, its part of a complete introduction to CF and tells you something how to act with different wind speeds.

the three points that ARE important (rule of thumbs) are:
-wind-speed on the ground needs to be less than max speed of canopy
-when performing standard CRW (so not competition jumping or big formations...) try to keep on flying right against the wind direction (note, this can change on different altitudes!)
- calculate approx exit point using highest wind speed and direction
Caren

Share this post


Link to post
Share on other sites
Wind Concerns:

1 - landing. You know the answer to this. What are you prepared to land in?

2 - Canopy Formations - Contact. Changing wind direction and turbulence are issues. Examples include wind shear (change of direction), turbulence from the lee sides of mountain ranges (i.e at Gap in France). You also have lift around Cumulous clouds and above thermal sources on the ground.

You need to consider:
- absolute wind speed - i.e. getting dragged on landing because the wind is too strong to control your canopy is not good.
- changing wind speeds -> this can be in the form of turbulence and gusts. Too much of either on landing or whilst doing canopy formations is not good.

Going backwards in consistent winds doing CRW is OK up to a point IMHO.
Remember if you are flying directly along the wind line, the relative closing speeds should be the same regardless of the wind speed. It changes a bit when it is slightly cross wind - the physics does not necessarily match the practice - so leave a bit more margin for error when approaching and setting up on a formation.

I have done an 8 way training camp with 50 to 70 knot uppers (they were constant, consistent winds), but had little wind on landing. Your spotting skills have to be better!

The answer is dependant on many factors:
- size of the formation (bigger means more conservative)
- type of CRW (rotations can handle more than sequential - planes are more solid than stacks or offsets)
- wing loadings (can handle more with higher loadings)
- experience (beginners should minimise risk to maximise safety and fundamental learning opportunity)
- etc.
Stay Safe - Have Fun - Good Luck

The above could be crap, thought provoking, useful, or . . But not personal. You decide.

Share this post


Link to post
Share on other sites
I should clarify to say that turbulance are caused in part by wind speed/direction. There are also other variables which can cause them. As an example, solar effects over fields or water.

I'm sorry, were you looking for the short answer?
Birdshit & Fools Productions

"Son, only two things fall from the sky."

Share this post


Link to post
Share on other sites
Hi everyone & thank you for all the information.

Quick question....

Quote

calculate approx exit point using highest wind speed and direction



Why not use an average wind speed & direction instead of the highest? Is this just for a little saftey margin?

Thanks again,
Andy

Share this post


Link to post
Share on other sites
Quote

Why not use an average wind speed & direction instead of the highest? Is this just for a little saftey margin?

Thanks again,
Andy



If your spot is long, you can always run back with the wind. If your spot is short, you will be blown past the dz and it's much harder to make up ground.
Birdshit & Fools Productions

"Son, only two things fall from the sky."

Share this post


Link to post
Share on other sites
Quote

Quote

Why not use an average wind speed & direction instead of the highest? Is this just for a little saftey margin?

Thanks again,
Andy



If your spot is long, you can always run back with the wind. If your spot is short, you will be blown past the dz and it's much harder to make up ground.



I'm not sure I agree with calculating the exit point based on the highest winds instead of using averages. If you've got very high winds at higher altitudes, but negligible winds at lower altitudes, you can easily be stuck long with not enough wind to get back. Not that landing off should be a big deal.

I average speed and direction and get pretty consistent results.


Share this post


Link to post
Share on other sites

Dude,

I'd love to! What are the dates?

If its just a weekend thing then it may be a bit far to come but if its a week then I could justify that to the Mrs. I'm also relocating from France to UK at the end of July but I'm sure she would also be fine with that B|B|B|

...seriousley mate what are the dates and I'll see if I can swing it???

Best regards,
Andy
PS. I got me a Lightning 193 that I'm planning on tuning a little B|

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

0